A known sheet conveyor apparatus includes a sheet support portion where one or more sheets are held, and a first roller for feeding the sheets, which are stacked on the sheet support portion, in a sheet conveyance direction. The sheet conveyor apparatus further includes a second roller, which is disposed downstream of the first roller in the conveyance direction, which is rotatable about a rotation axis extending in a widthwise direction of the conveyed sheet, and which serves to separate plural sheets one by one, and a holder, which is supported to be swingable about a rotation axis, and which rotatably supports the first roller.
The holder includes a transmission mechanism for transmitting rotation of the second roller about the rotation axis to the first roller. The transmission mechanism includes two pulleys rotatable together with the first roller and the second roller, respectively, and a belt stretched around the two pulleys. In the sheet conveyor apparatus, a rotational speed of a motor for rotating the second roller is controlled to adjust a pressing force of the first roller against the sheet such that the sheet is fed in the conveyance direction. Furthermore, the first roller may be pressed against the sheet by the weight of the holder and the first roller.